Nachiketas and immortality

I wrote in my earlier post what led me to the study of advaita.I was also eager to learn about Nachiketas.I had heard about nachiketas.Not much.I just knew that he was a small boy who featured in the upanishads.I had heard that Nachiketas was a philosopher who tried to unravel the mysteries of the after life.
One day,i logged on to the internet and typed 'nachiketas'.I got a flurry of links.I browsed for a bit and found myself staring at an English translation of the Katha Upanishad.First,there was the story of King Vajasravas which led to a conversation between Yama and Nachiketas.
Nachiketas asks Yama,"Please tell me what happens to a man after Death".I was shell shocked when i read that Yama tried to evade that question by offering Nachiketas many other boons like banglows,cattle and beautiful women.But Nachiketas remained stead fast and insisted that he be properly initiated on the after life.Yama agrred to it.
I was expecting a description on the lines of the Garuda Purana.But,i was surprised to find that it was आत्मा विद्या(atma vidya).आत्मा विचरम was what yama asked nachiketas to follow.Hinduism's most subtle concept..Atma vidya..
Hindu scriptures always instruct the seeker of knowledge to understand the difference between the आत्मा and the physical body.As long as man is under the impression that he is a mass of flesh and bones,he gets trapped in the cycle of births and deaths and for such a person,salvation is just a dream.When he realises that he is atma,he attains मोक्ष(heaven).The atma is pure and  is unaffected by the sufferings of the body.So when one realises that he is atma,man becomes free of desires.For,all the fruits of our efforts are for the body and not for the soul(atma).The body is often likened to the shirt men wear.When it becomes old,we simply throw it away.we don't cling on to it..The body is merely the shirt for the soul,a covering.Just as our body is invisible as long as we wear the shirt,so is the आत्मा as long as man is deluded by the thinking that "this body is me".The body is mortal,while the soul is immortal.When a person dies,it just means that the soul is liberated from that body.The soul then attaches itself to another body.This cycle of births and deaths goes on and on,as long as there is an attachment to the body.Once a man realises that"I am atma",he breaks the cycle of births and deaths and attains salvation.
This is not my philosophy.This can be found in the Bhagavadh Gita,Adi Shankara's texts and the Ramayana.
In the Gita,Lord Krishna begins आत्मा विद्या with the lines
"असोच्या  अन्वासोचास्थ्वं  प्रग्न्य  वाचंत्हू  बशाथे
गथाशूं अगाथा शूम्स्था नानू सोचंथी पंडिता हा
कुमाथि  महारथ आत्मा विद्यया"
Shankaracharya's texts like vivekashudamani are based on the difference between the soul and the body.In the Ramayana,the earliest Indian epic(known as आदि काव्यं)Hanuman consoles tara,vaali's wife(after vaali's death) with these words"The body is like a water bubble-stays for a very short duration.Its foolish to expect a bubble to last forever.The atma is like the ocean-ever lasting.So stop grieving about the death of your husband".For someone who has realized his Self,there is nothing to grieve about.For,Happiness and sorrow are merely states of the mind,or rather mind's creation.The atma is never affected by the turbulence of the mind.Switching states of happiness and sadness do not affect the self sufficient atma.
In Kathopanishad,Yama tells Nachiketas about immortality.It is not something concerning the body,but the soul.Once Self realization takes place,man becomes immortal -not in the way we read in fairy tales or "Harry Potter and the deathly Hallows", but in a more subtler way..I dont think I've the acumen to explain further.So,i just provide you the link to katha upanishad.
http://www.gayathrimanthra.com/contents/documents/Vedic-related/katha_upanishad.pdf
May peace prevail.